Oh, I'm sure I have.

A lot of what is rude or offensive versus light-hearted and meant to make someone smile depends on the recipient.

Someone might hear what you said and think it's nice that you think people of mixed ethnicity are attractive instead of thinking they're some sort of unacceptable love child. Lots of people still think that way.

If it makes you feel better, here's my story I can think of. A co-worker said she thought I was handsome. We were friends, so I didn't think it was rude when I told them, "Oh, Sharon likes some cream with her coffee."

She laughed and said (paraphrasing), "I like it with some sugar, but that means you'd still work."

I know I didn't offend her, but if someone else overheard the conversation, who knows what they thought? I'm sure it's offensive to someone on several levels.